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1.
Int J Mol Sci ; 24(7)2023 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-37047078

RESUMO

Although the exact mechanism of the pathogenesis of coronavirus SARS-CoV-2 (COVID-19) is not fully understood, oxidative stress and the release of pro-inflammatory cytokines have been highlighted as playing a vital role in the pathogenesis of the disease. In this sense, alternative treatments are needed to reduce the level of inflammation caused by COVID-19. Therefore, this study aimed to investigate the potential effect of red photobiomodulation (PBM) as an attractive therapy to downregulate the cytokine storm caused by COVID-19 in a zebrafish model. RT-qPCR analyses and protein-protein interaction prediction among SARS-CoV-2 and Danio rerio proteins showed that recombinant Spike protein (rSpike) was responsible for generating systemic inflammatory processes with significantly increased levels of pro-inflammatory (il1b, il6, tnfa, and nfkbiab), oxidative stress (romo1) and energy metabolism (slc2a1a and coa1) mRNA markers, with a pattern similar to those observed in COVID-19 cases in humans. On the other hand, PBM treatment was able to decrease the mRNA levels of these pro-inflammatory and oxidative stress markers compared with rSpike in various tissues, promoting an anti-inflammatory response. Conversely, PBM promotes cellular and tissue repair of injured tissues and significantly increases the survival rate of rSpike-inoculated individuals. Additionally, metabolomics analysis showed that the most-impacted metabolic pathways between PBM and the rSpike treated groups were related to steroid metabolism, immune system, and lipid metabolism. Together, our findings suggest that the inflammatory process is an incisive feature of COVID-19 and red PBM can be used as a novel therapeutic agent for COVID-19 by regulating the inflammatory response. Nevertheless, the need for more clinical trials remains, and there is a significant gap to overcome before clinical trials can commence.


Assuntos
COVID-19 , Animais , Humanos , Peixe-Zebra/metabolismo , SARS-CoV-2/metabolismo , Síndrome da Liberação de Citocina , Citocinas/metabolismo , RNA Mensageiro , Proteínas de Membrana , Proteínas Mitocondriais
2.
Molecules ; 20(2): 2636-57, 2015 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-25654532

RESUMO

Gedunin, a natural limonoid from Meliaceae species, has been previously described as an antiinflammatory compound in experimental models of allergic inflammation. Here, we report the antiinflammatory and antinociceptive effects of gedunin in an acute model of articular inflammation induced by zymosan (500 µg/cavity; intra-articular) in C57BL/6 mice. Intraperitoneal (i.p.) pretreatment with gedunin (0.005-5 mg/kg) impaired zymosan-induced edema formation, neutrophil accumulation and hypernociception in mouse knee joints, due to decreased expression of preproET-1 mRNA and production of LTB4, PGE2, TNF-α and IL-6. Mouse post-treatment with gedunin (0.05 mg/kg; i.p.) 1 and 6 h after stimulation also impaired articular inflammation, by reverting edema formation, neutrophil accumulation and the production of lipid mediators, cytokines and endothelin. In addition, gedunin directly modulated the functions of neutrophils and macrophages in vitro. The pre-incubation of neutrophil with gedunin (100 µM) impaired shape change, adhesion to endothelial cells, chemotaxis and lipid body formation triggered by different stimuli. Macrophage pretreatment with gedunin impaired intracellular calcium mobilization, nitric oxide production, inducible nitric oxide synthase expression and induced the expression of the antiinflammatory chaperone heat shock protein 70. Our results demonstrate that gedunin presents remarkable antiinflammatory and anti-nociceptive effects on zymosan-induced inflamed knee joints, modulating different cell populations.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Cartilagem Articular/efeitos dos fármacos , Limoninas/farmacologia , Nociceptividade/efeitos dos fármacos , Osteocondrite/tratamento farmacológico , Animais , Cartilagem Articular/imunologia , Cartilagem Articular/patologia , Sobrevivência Celular , Endotelina-1/metabolismo , Mediadores da Inflamação/metabolismo , Articulação do Joelho/efeitos dos fármacos , Articulação do Joelho/imunologia , Articulação do Joelho/patologia , Ativação de Macrófagos/efeitos dos fármacos , Masculino , Camundongos Endogâmicos C57BL , Infiltração de Neutrófilos , Osteocondrite/imunologia
3.
Front Immunol ; 13: 1019201, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36248846

RESUMO

Regulation of inflammation is a critical process for maintaining physiological homeostasis. The λ-carrageenan (λ-CGN) is a mucopolysaccharide extracted from the cell wall of red algae (Chondrus crispus) capable of inducing acute intestinal inflammation, which is translated into the production of acute phase reactants secreted into the blood circulation. However, the associated mechanisms in vertebrates are not well understood. Here, we investigated the crucial factors behind the inflammatory milieu of λ-CGN-mediated inflammation administered at 0, 1.75, and 3.5% (v/w) by i.p. injection into the peritoneal cavity of adult zebrafish (ZF) (Danio rerio). We found that polymorphonuclear leukocytes (neutrophils) and lymphocytes infiltrating the ZF peritoneal cavity had short-term persistence. Nevertheless, they generate a strong pattern of inflammation that affects systemically and is enough to produce edema in the cavity. Consistent with these findings, cell infiltration, which causes notable tissue changes, resulted in the overexpression of several acute inflammatory markers at the protein level. Using reversed-phase high-performance liquid chromatography followed by a hybrid linear ion-trap mass spectrometry shotgun proteomic approach, we identified 2938 plasma proteins among the animals injected with PBS and 3.5% λ-CGN. First, the bioinformatic analysis revealed the composition of the plasma proteome. Interestingly, 72 commonly expressed proteins were recorded among the treated and control groups, but, surprisingly, 2830 novel proteins were differentially expressed exclusively in the λ-CGN-induced group. Furthermore, from the commonly expressed proteins, compared to the control group 62 proteins got a significant (p < 0.05) upregulation in the λ-CGN-treated group, while the remaining ten proteins were downregulated. Next, we obtained the major protein-protein interaction networks between hub protein clusters in the blood plasma of the λ-CGN induced group. Moreover, to understand the molecular underpinnings of these effects based on the unveiled protein sets, we performed a bioinformatic structural similarity analysis and generated overlapping 3D reconstructions between ZF and humans during acute inflammation. Biological pathway analysis pointed to the activation and abundance of diverse classical immune and acute phase reactants, several catalytic enzymes, and varied proteins supporting the immune response. Together, this information can be used for testing and finding novel pharmacological targets to treat human intestinal inflammatory diseases.


Assuntos
Leucócitos , Proteoma , Peixe-Zebra , Proteínas de Fase Aguda , Animais , Carragenina/metabolismo , Glicosaminoglicanos , Humanos , Inflamação/induzido quimicamente , Neutrófilos/metabolismo , Plasma/metabolismo , Proteômica , Peixe-Zebra/metabolismo
4.
Sci Total Environ ; 813: 152345, 2022 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-34942250

RESUMO

Despite the significant increase in the generation of SARS-CoV-2 contaminated domestic and hospital wastewater, little is known about the ecotoxicological effects of the virus or its structural components in freshwater vertebrates. In this context, this study evaluated the deleterious effects caused by SARS-CoV-2 Spike protein on the health of Danio rerio, zebrafish. We demonstrated, for the first time, that zebrafish injected with fragment 16 to 165 (rSpike), which corresponds to the N-terminal portion of the protein, presented mortalities and adverse effects on liver, kidney, ovary and brain tissues. The conserved genetic homology between zebrafish and humans might be one of the reasons for the intense toxic effects followed inflammatory reaction from the immune system of zebrafish to rSpike which provoked damage to organs in a similar pattern as happen in severe cases of COVID-19 in humans, and, resulted in 78,6% of survival rate in female adults during the first seven days. The application of spike protein in zebrafish was highly toxic that is suitable for future studies to gather valuable information about ecotoxicological impacts, as well as vaccine responses and therapeutic approaches in human medicine. Therefore, besides representing an important tool to assess the harmful effects of SARS-CoV-2 in the aquatic environment, we present the zebrafish as an animal model for translational COVID-19 research.


Assuntos
COVID-19 , Glicoproteína da Espícula de Coronavírus , Animais , Feminino , Humanos , SARS-CoV-2 , Peixe-Zebra
5.
J Ethnopharmacol ; 241: 111970, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31128150

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Jatropha curcas L. is a plant with high cultural significance for quilombola communities of Oriximiná (Pará State, Brazil). Although the plant is highly toxic, its seeds are used in these communities to treat tuberculosis and related diseases and symptoms. AIM OF THE STUDY: This study was designed to provide a scientific rationale for the traditional detoxification method and use of J. curcas seeds in quilombola communities of Oriximiná. MATERIALS AND METHODS: J. curcas seeds were manually separated into testa, tegmen, endosperm, and embryo, and then methanolic extracts of each sample were prepared. The traditional preparation of J. curcas seeds consists of a water extract of endosperms that is known as "milk of pinhão-branco". The content of phorbol esters (PEs) in the extracts was analyzed by High-Performance Liquid Chromatography with Diode-Array Detection (HPLC-DAD). The cytotoxic activity was evaluated in human monocytic cell line THP-1 by Resazurin Reduction Assay, and antimycobacterial activity was assessed by determining Minimal Inhibitory Concentration (MIC) values against H37Rv and BCG strains using the Resazurin Microtiter Assay (REMA). RESULTS: The content analysis revealed that the distribution of PEs within the seeds is not homogeneous. High contents were found in tegmens (4.22 ±â€¯0.25-15.52 ±â€¯0.06 mg/g) and endosperms (1.61 ±â€¯0.07-5.00 ±â€¯0.42 mg/g), while concentrations found in testas and embryos were all below 0.5 mg/g. The traditional preparation derived from the endosperm of J. curcas contained significantly less PEs than the endosperms (0.01 ±â€¯0.005 mg/g). Against THP-1 cells, all the parts of the seed showed cytotoxic activity, while the traditional preparation was considered non-cytotoxic. Nevertheless, only the tegmen and endosperm of J. curcas were considered active against M. tuberculosis and M. bovis (MIC = 200 µg/mL). CONCLUSION: The results of this study indicated that the traditional processing performed by the quilombola people from Oriximiná is effective in reducing the toxicity of J. curcas seeds. Although inactive against mycobacteria, the extensive use of the traditional preparation and its low toxicity encourage further studies to investigate other biological activities.


Assuntos
Jatropha , Medicina Tradicional , Ésteres de Forbol , Extratos Vegetais , Sementes/química , Antibacterianos/análise , Antibacterianos/farmacologia , Antibacterianos/toxicidade , Brasil , Sobrevivência Celular/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana , Mycobacterium bovis/efeitos dos fármacos , Mycobacterium bovis/crescimento & desenvolvimento , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/crescimento & desenvolvimento , Ésteres de Forbol/análise , Ésteres de Forbol/farmacologia , Ésteres de Forbol/toxicidade , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Extratos Vegetais/toxicidade , Células THP-1
6.
Int J Antimicrob Agents ; 48(6): 753-756, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27838279

RESUMO

Generic medicines were developed to increase population access to health treatment, to reduce costs and to allow drugs with the same outcomes to be purchased at lower prices. They are therapeutically equivalent to their brand-name counterparts and are interchangeable with them. However, the acceptance of generic medicines by physicians and general consumers is often affected by distrust related to quality and efficacy. In this study three different brands of generic amoxicillin were tested. The results showed that two of them were indistinguishable from the innovator in terms of microbiological potency; however, generic B was unable to reach the Brazilian Pharmacopoeia specifications for potency limits. In contrast, generic B was bioequivalent to the innovator amoxicillin in pharmacokinetic assessment and, surprisingly, generic A, which was approved in the microbiological potency assay, lacked pharmacokinetic equivalence compared with the innovator. Both tests, when used singly, may not be effective at detecting quality deviations in antimicrobial medicines, which indicates that pharmacokinetic tests in rats in association with microbiological potency assays are a valuable tool for post-marketing surveillance of generic antibiotics.


Assuntos
Amoxicilina/farmacologia , Amoxicilina/farmacocinética , Antibacterianos/farmacologia , Antibacterianos/farmacocinética , Medicamentos Genéricos/farmacologia , Medicamentos Genéricos/farmacocinética , Vigilância de Produtos Comercializados , Amoxicilina/administração & dosagem , Animais , Antibacterianos/administração & dosagem , Medicamentos Genéricos/administração & dosagem , Humanos , Masculino , Ratos Wistar
8.
Malar Res Treat ; 2012: 679090, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23097741

RESUMO

Artemisinin and its derivates are an important class of antimalarial drug and are described to possess immunomodulatory activities. Few studies have addressed the effect of artesunate in the murine malaria model or its effect on host immune response during malaria infection. Herein, we study the effect of artesunate treatment and describe an auxiliary mechanism of artesunate in modulating the inflammatory response during experimental malaria infection in mice. Treatment with artesunate did not reduce significantly the parasitemia within 12 h, however, reduced BBB breakdown and TNF-α mRNA expression in the brain tissue of artesunate-treated mice. Conversely, mefloquine treatment was not able to alter clinical features. Notably, artesunate pretreatment failed to modulate the expression of LFA-1 in splenocytes stimulated with parasitized red blood cells (pRBCs) in vitro; however, it abrogated the expression of ICAM-1 in pRBC-stimulated endothelial cells. Accordingly, a cytoadherence in vitro assay demonstrated that pRBCs did not adhere to artesunate-treated vascular endothelial cells. In addition, NF-κB nuclear translocation in endothelial cells stimulated with pRBCs was impaired by artesunate treatment. Our results suggest that artesunate is able to exert a protective effect against the P. berghei-induced inflammatory response by inhibiting NF-κB nuclear translocation and the subsequent expression of ICAM-1.

9.
Int Immunopharmacol ; 14(1): 82-93, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22709475

RESUMO

T lymphocytes are critical cells involved in allergy. Here, we report that the natural tetranortriterpenoid gedunin impaired allergic responses primarily by modulating T lymphocyte functions. The intraperitoneal (i.p.) administration of gedunin inhibited pleural leukocyte accumulation triggered by intra-pleural (i.pl.) challenge with ovalbumin (OVA) in previously sensitized C57BL/6 mice; this inhibition was primarily due to the impairment of eosinophil and T lymphocyte influx. Likewise, i.pl. pre-treatment with gedunin inhibited eosinophil and T lymphocyte migration into mouse lungs 24 h after OVA intra-nasal (i.n.) instillation. Pre-treatment with gedunin diminished the levels of CCL2, CCL3, CCL5, CCL11, Interleukin-5 and leukotriene B(4) at the allergic site. In vitro pre-treatment with gedunin failed to inhibit T lymphocyte adhesion and chemotaxis towards pleural washes recovered from OVA-challenged mice, suggesting that gedunin inhibits T lymphocyte migration in vivo via the inhibition of chemotactic mediators in situ. In vivo pre-treatment with gedunin reduced the numbers of CD69(+) and CD25(+) T lymphocytes in the pleura and CD25(+) cells in the thoracic lymph nodes 24 h after OVA i.pl. challenge. In accordance, in vitro treatment of T lymphocytes with gedunin inhibited α-CD3 mAb-induced expression of CD69 and CD25, proliferation, Interleukin-2 production and nuclear translocation of NFκB and NFAT. Notably, post-treatment of mice with gedunin reverted OVA-induced lung allergic inflammation by decreasing the T lymphocyte and eosinophil counts and the levels of eosinophilotactic mediators in bronchoalveolar lavage fluid. Our results demonstrate a remarkable anti-allergic effect of gedunin due to its capability to modulate T cell activation and trafficking into the airways.


Assuntos
Azadirachta/imunologia , Hipersensibilidade/tratamento farmacológico , Inflamação/tratamento farmacológico , Limoninas/administração & dosagem , Linfócitos T/efeitos dos fármacos , Animais , Antígenos CD/metabolismo , Antígenos de Diferenciação de Linfócitos T/metabolismo , Movimento Celular/efeitos dos fármacos , Células Cultivadas , Citocinas/metabolismo , Eosinófilos/imunologia , Hipersensibilidade/imunologia , Inflamação/imunologia , Subunidade alfa de Receptor de Interleucina-2/metabolismo , Lectinas Tipo C/metabolismo , Ativação Linfocitária/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Linfócitos T/imunologia
10.
Inflammation ; 35(2): 764-71, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21842373

RESUMO

The present study was carried out to investigate the anti-inflammatory effect of the hexane extract of the leaves from Clusia nemorosa G. Mey, called HECn, using carrageenan-induced mice pleurisy and cotton pellet-induced mice granuloma. Additionally, the ability of HECn to affect both neutrophil migration as viability was investigated by use of the Boyden chamber assay and flow cytometry, respectively. The HECn significantly inhibited exudation, total leukocytes and neutrophils influx, as well as TNFα levels in carrageenan-induced pleurisy. However, the extract not suppressed the granulomatous tissue formation in the cotton pellet-induced granuloma test. Experiments performed in vitro revealed that HECn on human neutrophils inhibited a dose-dependent manner the CXCL1-induced neutrophil chemotaxis. Furthermore, HECn also inhibited the chemoattraction of human neutrophils induced by formyl-methionyl-leucyl-phenylalanine (fMLP), leukotriene B4 (LTB4) and platelet activating factor (PAF) in a Boyden chamber. However, this same treatment not was able to induce apoptosis. The results obtained in this study showed that the extract from leaves of C. nemorosa possess a potent inhibitory activity in acute model of inflammation, being the effects mediated, in part, by inhibition of neutrophil responsiveness. These results indicate that C. nemorosa could be a good source for anti-inflammatory compounds.


Assuntos
Anti-Inflamatórios/farmacologia , Clusia , Granuloma/tratamento farmacológico , Extratos Vegetais/farmacologia , Pleurisia/tratamento farmacológico , Animais , Apoptose/efeitos dos fármacos , Carragenina , Células Cultivadas , Quimiotaxia de Leucócito/efeitos dos fármacos , Fibra de Algodão , Granuloma/induzido quimicamente , Granuloma/imunologia , Humanos , Camundongos , Neutrófilos/imunologia , Neutrófilos/fisiologia , Fitoterapia , Folhas de Planta , Pleurisia/induzido quimicamente , Pleurisia/imunologia , Fator de Necrose Tumoral alfa/biossíntese
12.
Int Immunopharmacol ; 11(1): 1-11, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20951667

RESUMO

We have previously described the anti-allergic activities of a pooled fraction of tetranortriterpenoids (TNTPs) containing 6α-acetoxygedunin, 7-deacetoxy-7-oxogedunin, andirobin and methyl angolensate isolated from the seeds of Carapa guianensis. In the present study, we performed in vitro studies in order to elucidate the mechanisms by which TNTPs present their anti-allergic effects and to identify the bioactive compound(s) present in such fraction. Here, we show that in vitro incubation of eosinophils with the pooled TNTP fraction, as well as with each one of the five isolated tetranortriterpenoids, impaired the adhesion of eosinophils to tumor necrosis factor-α (TNF-α)-primed tEND.1 endothelial cells. Furthermore, the individual or pooled TNTPs impaired CCL11/eotaxin-mediated chemotaxis. By contrast, pooled TNTPs failed to inhibit adhesion and chemotaxis of T lymphocytes. However, TNTPs were able to impair anti-CD3 monoclonal antibody-induced T cell proliferation and the expression of CD25 and CD69. These data suggest that TNTPs prevent T cell activation. Pretreatment of splenocytes with the pooled TNTP fraction, as well as with each one of the five isolated TNTPs, inhibited ovalbumin (OVA)-induced in vitro production of interleukin-2, chemokine (C-C motif) ligand 11 (CCL11) and regulated on activation normal T cell expressed and secreted (RANTES, also known as CCL5). TNTPs (except 6α-acetoxygedunin) also impaired nuclear factor-κB (NFκB) nuclear translocation in OVA-challenged splenocytes. Taken together, these results demonstrate that the anti-allergic effects of TNTPs isolated from C. guianensis might rely on their ability to inhibit eosinophil migration, as well as the activation of T lymphocytes, which is shared by the five isolated TNTPs.


Assuntos
Eosinófilos/efeitos dos fármacos , Fatores Imunológicos/farmacologia , Limoninas/farmacologia , Meliaceae/química , Linfócitos T/efeitos dos fármacos , Animais , Adesão Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Quimiotaxia de Leucócito/efeitos dos fármacos , Quimiotaxia de Leucócito/imunologia , Células Endoteliais/citologia , Células Endoteliais/imunologia , Eosinófilos/citologia , Eosinófilos/imunologia , Citometria de Fluxo , Fatores Imunológicos/isolamento & purificação , Fatores Imunológicos/toxicidade , Limoninas/isolamento & purificação , Limoninas/toxicidade , Camundongos , Camundongos Endogâmicos C57BL , Estrutura Molecular , Ovalbumina/imunologia , Ratos , Ratos Wistar , Sementes/química , Baço/citologia , Baço/imunologia , Linfócitos T/citologia , Linfócitos T/imunologia
13.
J Leukoc Biol ; 87(5): 885-93, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20219953

RESUMO

IL-13 and eotaxin play important, inter-related roles in asthma models. In the lungs, CysLT, produced by the 5-LO-LTC4S pathway, mediate some local responses to IL-13 and eotaxin; in bone marrow, CysLT enhance IL-5-dependent eosinophil differentiation. We examined the effects of IL-13 and eotaxin on eosinophil differentiation. Semi-solid or liquid cultures were established from murine bone marrow with GM-CSF or IL-5, respectively, and the effects of IL-13, eotaxin, or CysLT on eosinophil colony formation and on eosinophil differentiation in liquid culture were evaluated, in the absence or presence of: a) the 5-LO inhibitor zileuton, the FLAP inhibitor MK886, or the CysLT1R antagonists, montelukast and MK571; b) mutations that inactivate 5-LO, LTC4S, or CysLT1R; and c) neutralizing mAb against eotaxin and its CCR3 receptor. Both cytokines enhanced GM-CSF-dependent eosinophil colony formation and IL-5-stimulated eosinophil differentiation. Although IL-13 did not induce eotaxin production, its effects were abolished by anti-eotaxin and anti-CCR3 antibodies, suggesting up-regulation by IL-13 of responses to endogenous eotaxin. Anti-CCR3 blocked eotaxin completely. The effects of both cytokines were prevented by zileuton, MK886, montelukast, and MK571, as well as by inactivation of the genes coding for 5-LO, LTC4S, and CysLT1R. In the absence of either cytokine, these treatments or mutations had no effect. These findings provide evidence for: a) a novel role of eotaxin and IL-13 in regulating eosinophilopoiesis; and b) a role for CysLTRs in bone marrow cells in transducing cytokine regulatory signals.


Assuntos
Quimiocina CCL11/metabolismo , Eosinófilos/citologia , Hematopoese/fisiologia , Interleucina-13/metabolismo , Receptores de Leucotrienos/metabolismo , Transdução de Sinais/fisiologia , Animais , Células da Medula Óssea/metabolismo , Diferenciação Celular/fisiologia , Eosinófilos/metabolismo , Feminino , Masculino , Camundongos , Microscopia Confocal , Regulação para Cima
15.
Fiocruz/INCQS; .
Não convencional em Português | Arca: Repositório institucional da Fiocruz | ID: arc-60469

RESUMO

O uso indiscriminado de antimicrobianos tem favorecido a seleção de bactérias resistentes que antes relacionadas a infecções nosocomiais passam a ser associadas a infecções comunitárias, tornando-se uma ameaça a saúde pública. As Enterobactérias aparecem como responsáveis por grande parte das infecções comunitárias e infecções relacionadas a assistência à saúde (IRAS). A hiperprodução de ß lactamases de espectro estendido (ESBL) e a produção de carbapenemases são os principais mecanismos envolvidos na resistência dentro do grupo. Objetivo: Avaliar a presença de genes que conferem resistência a antimicrobianos entre espécies de enterobactérias provenientes de infecções comunitárias e IRAS. Metodologia: 1) Seleção das amostras clínicas (ambulatorial e hospitalar) de enterobactérias no período entre mar/2021 e fev/2023. Disponibilizadas pelo Laboratório de Análises Clínicas Neolab e do Hospital Federal da Lagoa. 2) Os testes de susceptibilidade aos antimicrobianos foram realizados pelo Vitek. A produção de ß-lactamases foi avaliada pelo método de Nitrocefin. A confirmação de ESBL foi realizada pelo teste de sinergismo por disco-difusão e para triagem de carbapenemases foi efetuada provas com inibidores e potenciadores enzimáticos. 3) Extração e purificação de DNA genômico. Detecção dos genes de resistência por qPCR-HRM. Sequenciamento será realizado pela técnica de MLST. Resultados preliminares: Das 86 cepas recebidas, a espécie mais frequente foi a K. pneumoniae (n=57). Todas as cepas foram positivas para produção de ß-lactamase. Para avaliação de ESBL, os testes obtiveram resultados positivos em 60,47% das amostras. A confirmação por qPCR-HRM está em andamento. 48,84% dos isolados apresentaram perfil de resistência aos carbapenêmicos e que serão confirmadas por métodos moleculares. Os testes de triagem indicaram que 45,24% dos isolados são produtoras da enzima KPC; 11,90% dos isolados são produtoras de uma metalo-ß-lactamase; 40,48% dos isolados tiveram resultados inconclusivos que aguardam confirmação. Entre os isolados positivos para metalo-ß-lactamase, 60% obtiveram resultado positivo para o gene blaNDM. Todos os isolados positivos para KPC na triagem obtiveram confirmação no teste molecular. Foi encontrado 1 isolado carreando os dois genes. Conclusão: O estudo permitirá determinar os tipos de genes de resistência circulantes e a potencial disseminação para outras espécies e para o ambiente comunitário e avaliar a presença desses genes a clones específicos.

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